The present invention relates to a leg restraint device for side-seated vehicle occupants. In particular, the invention relates to a leg restraint device for side-seated occupant of, for example, corporate aircraft of the type offering side-facing seats for passengers. The disclosed invention has application in any form of vehicle transportation where passenger or occupant seats may be mounted in a side-facing orientation in relation to the direction of forward travel of the vehicle, such as an aircraft. The FAA has released Policy PS-ANM-25-03-R1 requiring leg flail prevention for occupants seated in side-facing seats when the occupant's upper leg is restricted by contact with the seat itself and/or with an interior component. In order to provide adequate occupant protection, the lower legs must also be restricted in a similar manner to avoid upper leg femur bone torsion. Thus, there is a need for a device that will provide this lower leg support during a dynamic event such as a crash.
Violent or abrupt deceleration can cause high g-force lateral loading on a side-facing passenger, causing lateral leg movement and leg rotation about the knee and femur. This can cause dislocations, muscle and tendon injuries and fractures due to the restraint exerted on the passenger's torso by seat belts and/or arm rests while the legs are unrestrained. However, belts or similar restraints on the legs are not advisable due to the additional time needed to remove the restraints, as well as the possibility that injuries to the passenger may make it difficult for either the passenger or emergency personnel to remove such restraints.
Therefore, there is a need for a type of leg restraint that provides protection to the legs of side-facing seat occupants in the event of a crash or other rapid deceleration, while not inhibiting rapid egress from the seat after the event.
The leg flail prevention device disclosed in this application deploys automatically and is designed to be triggered by the same sensor and trigger that is used to deploy inflatable shoulder harness air bags also installed on the side-facing seat. As such, for installations that restrict the side-facing occupant's upper legs in the forward direction, the automatic leg flail prevention device is utilized to introduce the higher level of occupant protection. In the embodiment disclosed in the application, a linear restraint panel presents the main restriction to the occupant's lower legs to prevent leg flail. This restraint panel is deployed by the inflation force of an attached air bag. Once the air bag deploys the restraint panel, the portion of the air bag attached to the restraint panel further inflates between the restraint panel and the leg to cushion the impact of the occupant's legs with the restraint panel.